Construction of single-injection vaccine using new time-controlled release system

Single-injection vaccines may overcome issues, such as high cost and poor patient compliance, of the multi-bolus regimes dominantly used in vaccination. However no such vaccine has been commercialized because time-controlled release, an unconventional release kinetics, is difficult to achieve. Here a new time-controlled release system using dynamic layer-by-layer (LBL) film as erodible coating was used to design single-injection vaccine. Unlike commonly used degradable polymers, dynamic LBL film disintegrates at a constant rate, thus allowing distinct pulsatile release of antigen at predetermined intervals. The release pattern of the single-injection vaccine mimics closely to that of ordinary multi-dose regimes. It elicits both humoral and cellular immune responses which are comparable to or even stronger than the corresponding multi-dose regime. In addition, it inhibits tumor growth more effectively. The new vaccine will not only improve patient compliance but also therapeutic outcome.